FIELD W 



Column 68 



but is the dose causing minimum response [minimum kill. Criterion 20 with Symbol P] or the 

 dose just lower than the dose causing any deaths [MTD, Criterion 21 with Symbol P]. Finally, 

 Symbol P is used when Criterion 21 is used to evaluate a test compound on the basis of the 

 dose level just below the threshold dose causing a toxic response other than "death" [re- 

 garding MTD as the maximum dose tolerated without causing non-lethal toxic effects, as 

 well as without causing death , prohibiting its use]. ) 



Questionable Response 



The occurrence or non- occurrence of the response coded in Field T (non-toxic response, 

 non-lethal toxic response, or death), as reported by the author, is questionable, due to 

 limiting factors of the test method and observation. This symbol should be used only 

 rarely and ordinarily only when the author has expressed doubts and reasons for the doubts 

 as to whether the evidence is valid for the response being positive or negative. 



Second use of Field W: 



Information about Slope of the 



Dosage-response Curve 



Information about the slope of the dosage-response curve is included with the original data. 

 Reference to the Code Sheet should be made for this information. (When coding Symbol * 

 In Field W, the written abstract of the field should include the information about the slope, 

 as defined and discussed in the Key. ) 



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